Insulated terminal connector



y 1953 D. J. CRIMMINS ETAL INSULATED TERMINAL CONNECTOR Filed Dec. 8, 1959 5 Sheets-Sheet l IN VENTORS.

DAV/0 CP/MMIIVS f/AAOLD 5. Amer/1V ATTOE/VE )f July 23, 1963 D, J. CRlMMiNS ETAL 3,098,688

INSULATED TERMINAL CONNECTOR 3 Sheets-Sheet 2 Filed Dec. 8, 1959 I I ,1 i m Z. .nmmlllllllf 2 wnm-sy 2.; 4a I 4 a INVENTORS.

DAV/D./- CP/MM/NS A2040 Edi/A277 ATTORNEY.

July 23, 1963 D. J. CRIMMINS ETAL INSULATED TERMINAL CONNECTOR Filed Dec. 8, 1959 5 Sheets-Sheet 3 IN VEN TORS. DA V/D (k/MM/lV-S 644E040 5. M41? 77/V 3,0%,688 INfiULATED TERMINAL CONNECTOR David J. Crirnmins, Nutley, and Harold B. Martin, Roselle, N..l., assignors to The Thomas & Bette Cm, Elizabeth, Nit, a corporation of New Jersey Filled Dec. 8, 1959, Ser. No. 858,266 2 Claims. (Cl. SIN-223) The invention relates to electrical connector and more particularly to a terminal connector of the insulated sleeve type adapted to be secured, as by means of a crimping operation thereon, on a bare end portion of insulated, multi-strand conductors, as exemplified in Frey Patent No. 2,769,965, issued November 6-, 1956.

More specifically, the invention resides in an insulated terminal connector of the apertured tongue type including a wire-barrel portion coextensive therewith, which is particularly adapt-ed for use in abnormally high and low temperature environments.

The invention resides in a terminal connector construction, an insulating sleeve of polytetrafluoroethylene, plastic initially frictionally secured on the wire barrel portion of the connector, and the method of and apparatus for subsequently anchoring the insulating sleeve on the connector in partial cold plastic flow relation, in response to a squeeze pressure operation directly thereon, whereby to crimp the connector on a bare end portion of an insulated, multi-strand conductor.

While polytetrafluoroethylene plastic, commercially available under the trademark Teflon, has been recognized for its stability in abnormally high and low temperature environments, as, for example, plus 500 degrees F. and minus 350' degrees F., it was not feasible heretofore to crimp a terminal connector on the bare end portion of an insulated, multistrand conductor in approved manner through an insulating sleeve of Teflon with a squeeze pressure tool or die, without rupturing, piercing, splitting or otherwise impairing the same.

Applicants discovered that a terminal connector could be crimped, in approved manner, on a bare end portion of an insulated multiastrand conductor by deforming the same through an insulating sleeve of Teflon, frictionally fitted on the wire-barrel end portion thereof, by controlling the cold flow of the Teflon in localized areas lengthwise thereof throughout its circumference by means of a pair of complementary die members having a cavity configuration specifically designed for the purpose.

The principal object of the invention is to provide an insulated terminal connector of the character herein described which is not subject to the above-noted disadvantages.

A further object of the invention is to provide a terminal connector having a plastic insulating sleeve frictionally fitted on the Wire-barrel portion thereof which remains stable in abnormally 'high and low temperature environments.

Another object of the invention is to provide a terminal connector having an insulating sleeve of Teflon frictionally fitted on the Wire-barrel portion thereof which may be crimped on a bare end portion of an insulated, multistrand conductor directly through its insulating sleeve without piercing, splitting or otherwise damaging the same.

A further object of the invention is to provide a terminal connector of the character specified in which an insulating sleeve, frictionally fitted on its wire-barrel end portion, comprises a stable plastic material which is not affected by abnormally high or low temperatures and which does not have an appreciable resistance to cold plastic flow in response to .a crimping operation thereon.

Another object of the invention is to provide a terminal connector of the character specified in which \a portion, of

ice

its wire-barrel end is adapted for receiving a portion of a plastic insulating sleeve, frictionally mounted thereon, in cold plastic flow anchored relation in response to a crimping operation directly thereon.

A further object ofthe invention is to provide a ternunal connector of the character specified wherein a plastic insulating sleeve is mechanically anchored in cold plastic flow relation on an intermediate soft metal sleeve, and said soft metal sleeve mechanically anchored to the wire barrel portion of said terminal connector by cold plastic flow of a portion of said insulating sleeve in response to a single crimping operation on said insulating sleeve.

I With the above and other objects in view, the inventron resides in'the herein described terminal connector, its correlated plastic insulating sleeve, the method of anchoring the insulating sleeve thereon in cold plastic flow relatron, and the method of and apparatus for crimping the msulated connector on a bare end portion of an insulated multi-strand conductor directly through. its insulating sleeve as set forth in the appended claims. The invention, both as to its organization and method of operation, together with additional objects and advantages thereof, being best understood from the following description of a specific embodiment thereof, when taken in connection with the accompanying drawing, in which:

FIG. 1 is a top plan view of an insulated terminal connect-o-r as secured by a squeeze pressure operation'on a bare end portion of an insulated, multi-strand conductor in accordance with the invention;

FIG. 2 is a view in side elevation of the terminal conhector shown in FIG. 1; f'

FIG. 3 is an explodedview in perspective showing the construction of the elements comprising the terminal connector per se, and its correlated plastic insulating sleeve;

FIG. 4 is a longitudinal sectional view of the insulated terminal connector assembly;

FIG. 5 is a longitudinal sectional view of the insulated terminal connector assembly as crimped on a bare end portion of an insulated, multi-strand conductor, showing the manner in which the plastic insulating sleeve is mechanically anchored to the elements of the connector per se, in accordance with the invention;

FIG. '6 is a transverse sectional view taken on the line 66 of FIG. 5;

FIG. 7 is a similar view taken on the line 7-7 of FIG. 5;

FIG. 8 is a transverse sectional view taken on the line 88 of FIG. 5;

FIG. 9 is a perspective view of the Teflon insulated terminal connector per se;

FIG. 10 is an end view in elevation of a two-part matching die set per se, utilized in deforming the Teflon insulated terminal connector on the bare end portion of an insulated, multiastrand conductor in accordance with the invention; A

1G. 11 is a side view in elevation of the same;

FIG. 12. is a fragmentary sectional view taken on the line 12-12 of FIG. 11; and

FIG. 13 is a sectional view taken on the line 13-13 of FIG. 11.

Referring to the drawings, FIGS. 1 and 2 illustrate the subject terminal connector 20, substantially as it appears after being deformed to a predetermined extent and configuration on a bare end portion 22 of an insulated, multis trand conductor 24, by means of a complementary, matching die set 26, as hereinafter described.

As shown in FIG. 3, the terminal connector 20 comprises an apertured tongue portion 28, including a wirebarrel portion 30, integral therewith; an intermediate thin metal ee 32; a P s c ulat n lee .4 f po ytetrafluorethylene resin commercially known under the trade name Teflon, the metal elements of the terminal connector 20 being suitably plated with nickel, for example, to provide a heat resistant surface.

In accordance with the invention and with particular reference to FIG. 4, the inner peripheral surface of the wire barrel 38 is suitably scored or otherwise roughened, as at R, and the tree outer end thereof tapered inwardly to provide an unobstructed entrance opening 36, for the free intrusion of the bare conductor end portion 22 into the wirc-barrel 30. Moreover, the outer periphery of the wire-barrel 30 is provided with an annular groove 38, adjacent its inner end, having a flat bottom and diverging side Walls for a purpose to be presently described.

Further in accordance with the invention, the intermediate sleeve 32 of soft, conductive metal has a common wall thickness throughout its length and opposite end portions 40 and 42 of difierent internal and external diameters with a V-type, annular groove 44, therebetween, presenting a rounded bottom and diverging side walls having rounded margins and forming a corresponding angular shoulder 46, about the inner periphery thereof. As best shown in FIGS. 3 and 4, the length of the reduced end 40 of the intermediate sleeve 32 is equal to the length of the wire barrel portion 30 between its free end and the nearest edge of the annular groove 38 therein, and the inner diameter of the said reduced end 40 substantially equal to the outer diameter of the Wire-barrel 30, whereby the reduced end 40 of the intermediate sleeve 32 is adapted to be frictionally secured on the wireabarrel 30, with its charnfered end 36 in abutment with the annular shoulder 46 within the sleeve 30. Thus the annular groove 38 adjacent the opposite end of the wire-barrel 30 remains fully exposed and the end portion 42 of the intermediate sleeve 32 disposed beyond the wire-barrel 30,

for a purpose now to be described.

With the intermediate sleeve 32 secured on the Wirebarrel 30, the terminal connector 20 is thereafter preinsulated and thus completed for use by frictionally securing the plastic insulating sleeve 34 of Teflon on the intermediate sleeve 32 by stretching the same thereover by means of a force fit, the length of the Teflon sleeve 32 being such that its inner end extends over and beyond the annular groove 38, in the wire-barrel 30, and its opposite end, beyond the free end portion 42 of the intermediate sleeve 32, as clearly shown in FIG. 4.

Referring now to FIGS. 5, '6, 7 and 8, the terminal connector 20 is secured on the insulated conductor 24, by intruding the stripped end portion 22 thereof into the wire-barrel 30 of the connector, from the extended free end of its correlated Teflon insulating sleeve 32, and the wire-barrel 30, deformed or crimped thereon indirectly by means of the matching die-set 26, comprising complementary halfasections 48 land 50, including a con nector-onienting and plastic flow-restraining end plate 54, secured to one side of the halfsection 48 by means of the screws 56, as shown in FIGS. 10 and 11, whereby the outer end portion of the intermediate metal sleeve 32 is deformed on the intruded end portion of the conductor insulation, and the opposite end portion of the metal sleeve 32, and the wire-bianrel 30 of the terminal connector 20 deformed or crimped simultaneously on the bare conductor end portion 22, directly through the Teflon insulating sleeve 34.

Further in accordance with the invention and as illustrated in FIGS. 10 through 13, the aforesaid die-set 26, comprises a pair of complementary half-sections 48 and 50, each having at lea-st one complementary cavity 52, in one face thereof, and a connector orienting and plasticfl ow restricting end plate 54, secured to one side of the half-section 48, by means of suitable screws 56, the end plate 54 being provided with a narrow, elongated slot 8, lengthwise thereof adapted to receive the tongue por- 28, of a terminal connector 28, therethrough when its insulated wire-barrel portion 30 is positioned in the cavity 52 in the half-section 48, for example, whereby to insure the application of squeeze pressure thereon in a plane perpendicular to its tongue portion 28.

As best shown in FIG. 11, the cavity 52 in each of the half-sections 48 and 50, when disposed in opposed matching relation, presents an opening 60 of elliptical configuration in cross-section with flat side Walls 62 tapering in a diverging manner from the beveled inner side edge 64 of each of the half-sections 48 and 58 to the beveled outer side edge 66 of the half-sections 48 and 50, in a plane perpendicular to the slot 58 in the attached end plate 54, as clearly indicated by the arrow 68 in FIG. 12.

The opposed elliptical surfaces 70 defining the opening 60 also taper in a diverging manner lengthwise thereof but the plane of the slot 58 in the end plate 54, and in an opposite direction from the beveled end 66 of the opening 60 to its opposite beveled end 64, as indicated by the arrow 72 in FIG. 13, the overall width of the half-sections 48 and 58 relative to the length of the insulated wire-barrel portion 30, to be deformed therebetween, being such, in a specific size of connector, that approximately onefourth of the length of the Teflon insulating sleeve 34, extends beyond the beveled outer end 66 of the elliptical opening 60, as exemplified schematically in FIGS. 12 and 13.

In the crimping or deformation of terminal connectors of a smaller size, the length of the elliptical opening 68 in the die half-sections 48 and 50 may be substantially equal to the length of the Teflon insulating sleeve 34 on the wire barrel 30 of such smaller terminal connectors.

From the foregoing description, taken in connection with FIGS. 12 and 13, it will be readily apparent that the longitudinal tapered elliptical opening 60 formed between the half-sections 48 and 50 of the die-set 26 provides for deformation of a Teflon insulating sleeve to a predetermined configuration in response to a uniform, predetermined squeeze pressure thereon in planes normal to each other and tapering outwardly in opposite directions, whereby controlled cold plastic flow lengthwise of the elliptical opening 60 is obtained.

In deforming or crimping the Teflon insulated wirebarrel portion 30 of the terminal connector 20 on the bare end portion 22 of the insulated, multi-strand conductor 24, in an outwardly tapering manner longitudinally and transversely thereof in opposite directions throughout a major portion of the length of the Teflon insulating sleeve 34, as exemplified in FIGS. 12 and 13, controlled cold plastic flow of the Teflon insulating sleeve 34 occurs from the outer beveled end 66 of the elliptical opening '60 formed between the half-sections 48 and 58 to the opposite inner beveled end 64 of the opening 68, where cold plastic flow of the Teflon sleeve 34 is restricted by the end plate 54 secured to the half-section 48, as best shown in FIG. 10. At the same time, limited transverse cold flow or spreading of the Teflon sleeve 34 also occurs substantially in a diverging manner from its inner end toward its outer end under control of the tapered, elliptical opening 60, in the matching die set 26, whereby the cold flow of the Teflon is forced radially into the annular V-groove 44 about the intermediate metal sleeve 32, and also into the annular groove 38 adjacent the inner end of the wire-barrel 30 of the terminal connector 20, to provide an annular keying action therebetween. Thus, the Teflon insulating sleeve 34 is anchored to the intermediate metal sleeve 32 of the terminal connector 20, and the intermediate metal sleeve 32, anchored to the wire-barrel portion 38 of the connector 28, indirectly through the crimped Teflon insulating sleeve 34, by virtue of the annular keying of its inner end portion to the wire-barrel 30, of the terminal connector 20.

The foregoing method of controlling cold plastic flow of the Teflon insulating sleeve 34 by a tapered deformation thereof in planes normal to each other, prevents the rupturing, piercing, splitting or undue elongation thereof by reason of the fact that in confining the Teflon sleeve substantially between the die sections 48 and 50, the Teflon sleeve is nevertheless free to a limited extent to flow lengthwise thereof in response to squeeze pressure applied on the die sections 48 and 50, and this limited cold plastic flow utilized for the purpose of mechanically securing the same on the intermediate sleeve 32, and at the same time to the wire barrel 30 of the terminal connector 20, whereby the intermediate metal sleeve 32 is indirectly secured on the wire-barrel 30, against relative endwise movement, in oppositely tapered relation. At the same time, the outer end 42 of the intermediate sleeve 32 is deformed on the adjacent insulation covering of the conductor end portion intruded thereinto, with the outer end portion of the Teflon sleeve 34 extending over the insulation covering on the conductor 24, in annularly spaced relation, as best shown in FIG. 5.

While the invention has been illustrated and described with respect to one embodiment thereof, it is to be expressly understood that various changes and modifications may be made therein without departing from the inventive concept underlying the same. Therefore, the invention is not to be limited except as is necessitated by the scope of the appended claims.

What is claimed is:

-1. An electrical connection comprising in combination a terminal connector of the aperture tongue, wire-barrel type having an annular groove adjacent the inner end of said wire-barrel, a thin metal sleeve of uniform wall thickness having a reduced end portion terminating in an inclined annular shoulder defining a V-groove in cross section midway of the length of said sleeve, the reduced end of said thin metal sleeve being frictionally secured on said wire-barrel in partial telescopic relation, an insulating sleeve of polytetrafluoroethylene plastic frictionally secured on said thin metal sleeve in full telescopic relation with its opposite ends extending beyond the respective ends of said thin metal sleve and over the inner end of said wire-barrel, and an insulated, multi-strand conductor having a bare end portion thereof intruded into said thin metal sleeve from the outer free end of said insulating sleeve and said wire barrel deformed thereon indirectly through said thin metal sleeve and said insulating sleeve whereby said annular groove and said V-groove receive portions of said insulating sleeve in cold flow keying relation upon controlled deformation of said insulating sleeve in the plane of the tongue portion of said connector and in a plane normal thereto and tapering from the inner end of said insulating sleeve to a point adjacent the outer end thereof without undue elongation of said insulating sleeve, said outer end portion beyond said first taper being reversely tapered and presenting a slightly larger elliptical configuration than the inner end portion thereof.

2. An electrical terminal connector of the apertured tongue, wire barrel, insulated sleeve type having an annular groove adjacent the inner end of its wire barrel portion, an intermediate thin metal sleeve having a uniform wall thickness and a reduced end portion terminating in an inclined annular shoulder defining an annular V- groove therein midway of the length of said sleeve, said reduced end portion of said thin metal sleeve being secured on said wire barrel portion in partial telescopic relation short of said annular groove therein, and an insulating sleeve of polytetrafluoroethylene plastic frictionally secured on said thin metal sleeve in full telescopic relation with its opposite ends extending beyond the ends of said thin metal sleeve and over the inner grooved end of said wire barrel portion, the annular groove in said wire barrel and the annular V-groove in said thin metal sleeve being adapted for receiving portions of said insulating sleeve therein in cold flow relation whereby to anchor said insulating sleeve and said thin metal sleeve to said wire barrel portion upon deformation of said insulating sleeve in the plane of said apertured tongue and in a plane normal thereto and tapering outwardly from the inner end of said insulating sleeve to a point adjacent the outer end thereof, the outer end portion of said insulating sleeve, beyond said adjacent point, tapering inwardly therefrom and presenting an elliptical configuration, and the outer end portion of said thin metal sleeve adapted to shield the insulation adjacent a bare end portion of an intruded electrical conductor, said terminal connector and said intermediate thin metal sleeve being formed of ductile metal having a relatively hard, non-oxidizing, heat resistant metallic plating thereon.

References Cited in the file of this patent UNITED STATES PATENTS 2,333,046 Sabol Oct. 26, 1943 2,400,099 Brubaker et a1 May 14, 1946 2,749,529 Curtiss June 5, 1956 2,751,570 Broske June 19, 1956 2,769,965 Frey Nov. 6, 1956 2,802,257 Holtzapple Aug. 13, 1957 2,807,792 OKeefe et a1 Sept. 24, 1957 2,821,811 Sanders et a1. Jan. 28, 1958 2,839,595 Felts et al. June 17, 1958 FOREIGN PATENTS 497,739 France Sept. 24, 1919 410,253 lltaly Mar. 31, 1945 OTHER REFERENCES Industrial and Engineering Chemistry, September 1946, pages 871 through 877.

The Rubber Age and Synthetics, vol. 34, June 1953, pages 164 through 166. 

1. AN ELECTRICAL CONNECTION COMPRISING IN COMBINATION A TERMINAL CONNECTOR OF THE APERTURE TONGUE, WIRE-BARREL TYPE HAVING AN ANNULAR GROOVE ADJACENT THE INNER END OF SAID WIRE-BARREL, A THIN METAL SLEEVE OF UNIFORM WALL THICKNESS HAVING A REDUCED END PORTION TERMINATING IN AN INCLINED ANNULAR SHOULDER DEFINING A V-GROOVE IN CROSS SECTION MIDWAY OF THE LENGTH OF SAID SLEEVE, THE REDUCED 